}
  }

  private boolean hasRemaining() {
    return remaining() > 0;
  }

  private int remaining() {
    requireNonNull(seq); // safe as long as we call this only after checkOpen
    return seq.length() - pos;
  }

  /*
   * To avoid the need to call requireNonNull so much, we could consider more clever approaches,
   * such as:
   *

  }

  @Override
  public C first() {
    // requireNonNull is safe because we checked the range is not empty in ContiguousSet.create.
    return requireNonNull(range.lowerBound.leastValueAbove(domain));
  }

  @Override
  public C last() {
    // requireNonNull is safe because we checked the range is not empty in ContiguousSet.create.
    return requireNonNull(range.upperBound.greatestValueBelow(domain));
  }

    // requireNonNull is safe because we use indexes that were populated by the constructor.
    V value = requireNonNull(values[rowIndex][columnIndex]);
    return cellOf(rowKey, columnKey, value);
  }

  @Override
  V getValue(int index) {
    // requireNonNull is safe because we use indexes that were populated by the constructor.

    if (effectiveRange.isEmpty()) {
      empty = true;
    } else {
      /*
       * requireNonNull is safe because the effectiveRange operations above would have thrown or
       * effectiveRange.isEmpty() would have returned true.
       */
      C afterLower = requireNonNull(range.lowerBound.leastValueAbove(domain));
      C beforeUpper = requireNonNull(range.upperBound.greatestValueBelow(domain));

            super(id);
            this.projectScope = Objects.requireNonNull(projectScope);
            this.dependencyScopes =
                    Collections.unmodifiableSet(new HashSet<>(Arrays.asList(Objects.requireNonNull(dependencyScopes))));
        }

        @Override
        public ProjectScope projectScope() {
            return projectScope;
        }

   */
  final void init() {
    /*
     * requireNonNull is safe because this is called from the constructor after `futures` is set but
     * before releaseResources could be called (because we have not yet set up any of the listeners
     * that could call it, nor exposed this Future for users to call cancel() on).
     */
    requireNonNull(futures);

    // Corner case: List is empty.

        this.classifier = classifier;
        this.extension = requireNonNull(extension);
        this.packaging = requireNonNull(packaging);
    }

    @Override
    public String getClassifier() {
        return classifier;
    }

    @Override
    public String getDirectory() {
        return null;
    }

    @Override
    public String getExtension() {

      int j = findNextJ();
      if (j == -1) {
        nextPermutation = null;
        return;
      }
      /*
       * requireNonNull is safe because we don't clear nextPermutation until we're done calling this
       * method.
       */
      requireNonNull(nextPermutation);

      int l = findNextL(j);
      Collections.swap(nextPermutation, j, l);
      int n = nextPermutation.size();

    // be deleted.
    Map<K, @Nullable V> duplicates = null;
    int dupCount = 0;
    for (int i = 0; i < n; i++) {
      // requireNonNull is safe because the first `n` elements have been filled in.
      entryArray[i] = makeImmutable(requireNonNull(entryArray[i]));
      K key = entryArray[i].getKey();
      V value = entryArray[i].getValue();
      V oldValue = delegateMap.put(key, value);

    @Inject
    MavenDeployer(DefaultDeployer deployer, ConsumerPomArtifactTransformer consumerPomArtifactTransformer) {
        this.deployer = requireNonNull(deployer);
        this.consumerPomArtifactTransformer = requireNonNull(consumerPomArtifactTransformer);
    }

    @Override
    public DeployResult deploy(RepositorySystemSession session, DeployRequest request) throws DeploymentException {